Finite Element Analysis and Failure Mechanisms of Porous Biomaterial Architecture for Prosthetic Device

Abstract

Many researchers have studied that porous unit cell-based architecture design and fabrication by additive manufacturing technique is proven to achieve similar mechanical characterization of trabecular bone. In this article, the micro-stress-strain distribution and failure mechanisms of bio-metal at four different types of porous architecture, chosen as X, Star, Cross and Octet lattice structures, with defined pore size, are studied. The unit cell-based structures have been modeled using INTRALATTICE CAD software, with specific pore size, strut aspect ratio (radius/length) and unit cell size. INTRALATTICE is capable of an efficient unit cell shape modeling and part design. For linear and nonlinear finite element (FE) analysis of above porous architectures, commercial CAE ANSYS and HyperMesh software have been used. 1D Beam and 3D tetra elements have been used to model the structure under compressive loads. The finite element (FE) results of all the unit cell-based architectures have been compared and identify which architecture has less stiffness response during the compressive loads. Subsequently, the micro-stress-strain distribution behaviors of all four porous structures have been illustrated through Johnson-Cook (nonlinear) FE model. This methodology has been used for estimating the structural response and failure mechanisms of unit cell geometry. Consequently, the unit cell type and size were modified to encountered desired Young’s modulus and yield stress under compressive loading condition. At last of this investigation, to check the CAE software reliability, for which validation part has been done with previously reported literature, that was performed both experimental and FE study.